GENERA AND SPECIES. 141 



the body ; and there are no scales. In colour this rare fish is 

 silvery, and in length it does not exceed 30 inches. It straggles here 

 from the tropics, and made its appearance on the British list by 

 being left by the tide on a sandy shore. 



Trigla. Plates vii. and viii. COTTID&. 



52. lineatu, STREAKED GURNARD. Lateral ridges that slope 



forwards from back to abdomen ; lateral line with 

 serrated spines. Colour red above, white below. 



53. cuculus, RED GURNARD. Spiny ridge along base of dorsals ; 



lateral line with spineless plates. Colour red ; fins 

 red. 



54. hirundo, SAPPHIRINE GURNARD. Spines along base of dorsals ; 



lateral line unarmed. Colour brownish red ; pectorals 

 large and blue. 



55. gnrnardus, GREY GURNARD. Colour grey with or without white 



markings. 



56. l>ra, PIPER. Two flat triangular plates over the snout, 



giving it the appearance of being divided. 



57. obscura, LANTHORN GURNARD. Broad silvery stripe along the 



side marking oft" the red above from the white below. 



The Streaked Gurnard has from 9 to n spines in the first dorsal, 

 16 or 17 rays in the second, 16 rays in the anal, 12 in the caudal, 10 

 or ii in the pectorals, and a spine and 5 rays in the ventrals. At 

 the base of the pectorals it has three filaments, like the other species 

 of the genus. The lateral line has 66 toothed spines, being half the 

 number of the row of scales above it. The scales along the bases of 

 the dorsals are keeled. Down each side is a series of narrow, parallel 

 ridges that slope slightly forwards. The sides are banded with red ; 

 the dorsals and caudal are reddish brown, spotted and blotched, and 

 have red edges ; the pectorals are red, green, and blue. The length 

 reaches 14 inches. This fish lives near the ground, and feeds on fish 

 and crustaceans. Like our other gurnards it erects its dorsals when 

 touched, and grunts. *' These sounds," says Cunningham, " are pro- 

 duced in the air-bladder. That organ is entirely closed, and its walls 

 contain well- developed muscles, which, by their contraction, drive 

 the air from one part of the bladder to another. The air-bladder 

 consists of three portions, a larger central chamber and a smaller 

 chamber on each side, communicating with the central chamber at 

 the front end. At the hinder portion of the central chamber there 

 is a partition running in a slanting direction across it, and in the 

 middle of this partition there is a round opening. The air is pressed 

 to and fro through this opening, and so the sound is produced." 



The Red Gurnard has 8 or 9 spines in the first dorsal, 18 rays 

 in the second, 16 or 17 rays in the anal, 13 in the caudal, 10 in the 

 pectorals, and a spine and 5 rays in the ventrals. In the lateral 

 line are from 73 to 76 plates, which are higher than they are wide, 

 and have no spines. This fish is rose-coloured, the three filaments 

 being red with a yellow tinge. In length it reaches 18 inches. In 

 habits it resembles the Streaked Gurnard, and makes a similar noise 

 in a similar way. 



